Sliver condenser for drawing frames



June 11, 1968 c. s. BOFILL 3,387,339

SLIVER CONDENSER FOR DRAWING FRAMES Filed Sept. 14, 1964 INVENTOR.CARLQS SAM-E5 Bonn.

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ATTORNEY United States Patent 3,387,339 SLIVER C(lNDENfiER FOR DRAWINGFRAMES Carlos Salles Bofill, Provenza 226,

Barcelona, Spain Filed Sept. 14, 1964, Ser. No. 396,214 2 Claims. (Cl.119-150) This invention relates to drawing frames and the like andparticularly to a novel structure for delivering sliver to the calenderrolls.

In drawing frames normally used in spinning, the sliver, on leaving thedrafting rolls passes through a trumpet placed on a plate and is carriedto a pair of calender rolls after which the sliver is taken up in arevolving can in which it is laid out. For best operation of this step,it has been found advantageous to introduce the sliver in the calenderrolls at substantially the very point of tan- -gency of the latter,which is the point of contact of these rolls. In actual practice this isdiffioult since the trumpet must be placed so that its lower orifice isabove the point of tangency of the calender rolls as otherwise, due tothe thickness of the walls of this trumpet, it would be in contact withthe calender rolls and would score them.

Thus, normally, there is a certain length of sliver free between thelower orifice of the trumpet and the rolls, and if the orifice is wide,the sliver opens out or expands in this area, with a subsequentreduction of the amount of sliver that can be contained in the take-upcan. This is a pronounced disadvantage in modern high productionspinning plants. On the other hand, if the trumpet orifice is narrow,there is a degree of friction applied to the sliver which tends to holdthe sliver in the trumpet and causes the sliver to be pulled out by thecalender rolls which are pulling it downward, thereby causingirregularity in the yarn ultimately spun.

Moreover, with this usual arrangement, the trumpet has changes inposition due to the normal vibration of the machine which is also adisadvantage since it is desirable for the axis of the trumpet to bemaintained at a tangential angle with respect to both calender rolls atthe point of tangency of the rolls, and this requires periodic checkingof the positioning of the trumpet.

The present invention is concerned with certain improvements in drawingframes, by which the previously mentioned disadvantages are avoided andwhich also provide other important advantages, since, without danger ofscoring the rolls and without having to regulate the position of thetrumpet, they allow carrying the sliver virtually to the precise pointof tangency of the calender rolls without producing any change in thecross-section of the sliver, and this cross-section can be fixed bymeans of a strong compressive force exerted thereupon by the calenderrolls.

The improvement may include a special trumpet element made of nylon oranother material of similar characteristics of hardness, beingprincipally a prismatic body made up of two concave cylindrical faceswith a radius corresponding to that of the calender rolls, andconverging at a common lower edge and which has a conical perforation,with two tapers, whose base opens out in the fiat face of the planeopposite the said edge, with a relatively large taper and having in thelower half a cone of relatively reduced taper whose vertex coincideswith the center of the aforementioned edge, which is formed by theconvergence of the cylindrical faces.

This trumpet rests freely directly upon the calender rolls and on theircylindrical faces so that the orifice of the trumpet in the shape of acone is situated virtually at precisely the line of tangency of thecalender rolls. The upper flat face of the trumpet remains positioned3,387,339 Patented June 11, 1968 either below the opening in thecovering plate which carries the sliver, but without touching the plate.Such may be positioned at the same level as the upper face of thecarrying plate, resting or positioned with loosely in an opening in thisplate of such size as to correspond in shape.

In this way, the trumpet has a certain amount of freedom of movementwhich allows the automatic centering of the exit orifice of the trumpet,eliminating the need for adjusting the usual trumpet above the carryingplate and eliminating any danger of scoring the rolls. At the same time,the sliver is delivered to the calender rolls at virtually the precisetangential point of the calender rolls. This means that in this way thesliver enters the calender rolls with the same reduced cross-sectionthat it has on exiting from the trumpet orifice, without having anyopportunity to open out or expand. This provides the important advantagethat, if there is exerted on the calender rolls a reciprocal pressuresufiiciently large, the cross-section of the sliver becomes fixedpermanently due to the pressure to which it is subjected, and therebyachieving a much greater capacity of the take-up can over the usual. Theuniformity or consistency of the sliver is also increased, favoring itssubsequent handling and avoiding slack twist in subsequent operations,all of which makes for greater regularity in the yarn subsequentlyobtained.

The construction designed to carry out the invention will be hereinafterdescribed, together with other features thereof.

The invention will be more readily understood from a reading of thefollowing specification and by reference to the accompanying drawingforming a part thereof, wherein an example of the invention is shown andWhere- FIGURE 1 is a schematic longitudinal cross-sectional view,illustrating the sliver as it leaves the drafting elements of a drawingframe and the like, showing how it is carried to the point of tangencyof the calender rolls in accordance with the present invention,

FIGURE 2 is an enlarged perspective view of a device constructed inaccordance with the present invention, and

FIGURE 3 is a front elevation illustrating the rear section of suchdevice, with the front section removed, to show the interior of theassembled device.

As FIGURE 1 illustrates, the sliver 10 on leaving the last pair of rolls11 of the drafting means passes over a plate 12 which has an opening 13under which the calcuder rolls 14 are located for delivering the sliver10 to the can (not shown).

Usually, the opening 13 in the pate 12 is circular and the usual trumpetis mounted in it with its exit orifice positioned a given distance abovethe rolls 14. However, it is perferable that the opening 13 be madelarger and of such a shape as to allow its positioning with certainlooseness, and so that the upper face maye be at substantially the samelevel as the plate 12. The body 15 is essentially prismatic in shape,being constructed of nylon or other desirable material, and has lowercylindrical faces 16 with a radius corresponding to that of the calenderrolls 14, and which converge almost tangentially forming a lower edge17.

The body 15 has an internal recess in the general shape of a truncatecone as at 18, with a substantial taper, the base of which opens in theupper face of the body, and which has a lower second conical section 19with a lesser taper and whose vertex coincides with the center of thelower edge 17, forming an orifice 20 of relatively small size.

Preferably, and to facilitate the movement of the sliver through theinterior of the trumpet and to increase the effect of reduction of thecross-section of the sliver, the

upper conical perforation 18 is made with convex taper 21 and the lowerconical perforation 19 with a concave taper 22, the two conicalperforations being connected together in a smooth curve so that theinner surface of the trumpet progresses smoothly from the upper to thelower conical perforation and the lower perforation 19 is prolonged in anarrow cylindrical passage 23 terminating in the exit orifice 2%.

This body made in the way described includes a passageway having doubleconical portions whose upper-half portion 18 guides the sliver in thetrumpet and reduces the section of the sliver while the lower-halfportion 19, with its prolongation 23, acts as a second section reducingportion for the sliver.

The body 15 rests freely on its cylindrical faces 16 on the two calenderrolls 14 so that its lower edge with the exit orifice 2t coincidesalmost exactly with the line of tangency of the said rolls 14, and itsupper fiat face coincides with the opening of the funnel 18, at the samelevel as the upper-face of the carrying plate 12.

As can be seen in this arrangement, the sliver 10 is carrier to the verypoint of tangency of the rolls 14 eliminating that section of sliverwhich usually remains free between the exit orifice of the usual trumpetand the nip or pressure point (point of tangency) of the calender rolls.This eliminates the expansion of the sliver and also any possibility ofdistension but without any danger of scoring the surface of the rolls 14due to the perfect adaptation of the contact surfaces of the body 15 andthe roll surfaces.

The calender rolls 14 are preferably mounted on sup porting elementsconnected together and which are urged toward each other by tensioncreated by appropriate means, such as springs (not shown), so that thesaid tension is compensated by the mutual reaction of both rolls,without being transmitted to supporting elements on the machine. Thesliver thus receives strong compression which fixes the cross-section ofthe sliver as it exits from the device.

In addition to these results obtained by the functioning of the funnelaccording to the improvements described, the method of mounting thisfunnel offers certain advantages also, since by resting directly uponthe calender rolls 14, without any rigid connnection to the carryingplate 12, it automatically centers itself so that its axis is maintainedconstantly tangential to the two calender rolls 14. A similar result maybe obtained if the usual opening of the plate 12 is formed in the shapeand dimensions of the opening of the truncated conical portion 18 andpositioned so that its upper flat face is located below the level of thecarrying plate 12 without contacting it.

In actual practice, and in order to facilitate the cleaning of theinside of the funnel without danger of damaging the exit orifice 26,particularly when the sliver is stuck in the trumpet, or breaks insideit, the body 15 of the trumpet is made preferably in two halves 15, 15in a plane perpendicular to the lower edge 17, which is connectedtogether by screws 24 which are housed in bores 25 in both halves, or:by other suitable means.

While a preferred embodiment of the invention has been described usingspecific terms, such description is for illustrative purposes only, andit is to be understood that changes and variations may be made withoutdeparting from the spirit or scope of the following claims.

What is claimed is:

1. For use in drawing frames and the like having a plate for the sliverbeyond the exit of the sliver from the drafting elements, and calenderrolls which deliver the sliver to a can, the improvement including, anelement of essentially prismatic shape having, an upper flat face,lateral concave cylindrical faces below said upper face with a radiuscorresponding to the calender rolls converging at virtually a tangentialangle forming a lower edge, a passageway extending from said upper facethrough said lower edge formed by a surface curvilinear shape with anupper convex taper blending smoothly with a lower concave taperingportion, and an exit orifice of small dimensions, said exit orificeincluding a prolongation of the lower portions in a narrow cylindricalportion, whereby the element rests freely on its cylindrical faces uponthe two calender rolls so that the lower edge with exit orificecoincides with the line of tangency of the calender rolls.

2. The structure set forth in claim 1, wherein the element includes, twohalves in a plane perpendicularly divided with respect to the loweredge, and means joining the halves together.

References Cited UNITED STATES PATENTS 146,816 1/1874 Frye 19-l50146,881 l/l874 Dawson l9.25

549,956 11/1895 Canning 19-150 2,640,229 6/1953 Gwaltney l9l57 3,246,3704/1966 West 19l50 FOREIGN PATENTS 801,254 12/1950 Germany.

593,310 10/1947 Great Britain.

609,753 10/ 1948 Great Britain.

MERVIN STEIN, Primary Examiner. D. NEWTON, Assistant Examiner.

1. FOR USE IN DRAWING FRAMES AND THE LIKE HAVING A PLATE FOR THE SLIVERBEYOND THE EXIT OF THE SILVER FROM THE DRAFTING ELEMENTS, AND CALENDERROLLS WHICH DELIVER THE SILVER TO A CAN, THE IMPROVEMENT INCLUDING, ANELEMENT OF ESSENTIALLY PRISMATIC SHAPE HAVING, AN UPPER FLAT FACE,LATERAL CONCAVE CYLINDRICAL FACES BELOW SAID UPPER FACE WITH A RADIUSCORRESPONDING TO THE CALENDER ROLLS CONVERGING AT VIRTUALLY A TANGENTIALANGLE FORMING A LOWER EDGE, A PASSAGEWAY EXTENDING FROM SAID UPPER FACETHROUGH SAID LOWER EDGE FORMED BY A SURFACE CURVILINEAR SHAPE WITH ANUPPER CONVEX TAPER BLENDING SMOOTHLY WITH A LOWER CONCAVE TAPERINGPORTION, AND AN EXIT ORIFICE OF SMALL DIMENSIONS, SAID EXIT ORIFICEINCLUDING A PROLONGATION OF THE LOWER PORTIONS IN A NARROW CYLINDRICALPORTION, WHEREBY THE ELEMENT RESTS FREELY ON ITS CYLINDRICAL FACES UPONTHE TWO CALENDER ROLLS SO THAT THE LOWER EDGE WITH EXIT ORIFICECOINCIDES WITH THE LINE OF TANGENCY OF THE CALENDER ROLLS.